1. Field of the Invention
The present invention is directed to an orthotic brace and, more particularly, to an orthosis having modular component parts, such as a hip orthosis, that can address the postoperative treatment of a patient following hip arthoplatyies.
2. Description of Related Art
Orthotic management of hip joint compromise has been a challenge for orthopaedics, orthotists, and therapists when dealing with patients whose hip joints and their associated soft tissues, joint integrity, alignment, and bone and capsular components are compromised. A hip is a multidirectional joint capable of flexion, extension, internal and external rotation, adduction, and abduction. In addition to its mobility, the hip joint must absorb the force of full weight-bearing and provide stability to the pelvis both for standing and for single support during gait. Additionally, during walking, while one hip is stabilized, the opposite leg must have the strength, range of motion, and structural integrity to advance.
The hip joint is a synovial ball and socket joint that consists of the articulation of the spherical head of the femur with the cup-like shape of the acetabulum. An acetabular labrum attaches to the bony rim of the acetabulum and cups around the head of the femur to hold it firmly in place. Various ligaments add strength to the articulation of the hip joint and a large number of muscles act on the hip joint. The gluteus medius is primarily associated with abduction. Anterior fibers assist with flexion and internal rotation. Posterior fibers assist with extension and external rotation. These muscle groups stabilize the pelvis during a single leg support.
Frequently, these muscle groups are compromised when surgical procedures are performed at the hip joint, especially during a hip replacement surgery. A significant problem that occurs when a hip joint has been compromised is dislocation of the hip joint. Thus, the femoral head can be driven out of the acetabulum. The hip is most susceptible to posterior dislocation when it is flexed past 90°, internally rotated and adducted. Examples of this action occur in every day living, such as sitting on a low chair and leaning forward while putting weight on the affected hip joint and internally rotating when coming to a standing position. Thus, common activities of daily living, specifically excessive hip flexion with loaded extremity and internal rotation on the affected side, can cause dislocation. Anterior dislocation also occurs when a hip is externally rotated, abducted, and flexed and if, for example, a knee is subject to a force, such as accidentally hitting an object. The neck of the femur or the greater trochanter levers the femur out of the acetabulum. To avoid these problems, an orthosis must be able to effectively control the limits of extension and rotation in a patient who has experienced an anterior dislocation.
The assignee of the present invention has provided orthoses to control extension and external rotation with a line of “NEWPORT®” hip system products. See, for example, Team Management of Hip Revision Patients Using a Post-Op Hip Orthosis by Lima et al., Journal of Prosthetics and Orthotics, Vol. 6, No. 1, Winter/1994.
An example of an orthotic hip support can be found in U.S. Pat. No. 5,830,168, while a safety device to assist movement of a person can be found in U.S. Pat. No. 5,361,418. An orthopedic hip and leg abductor is disclosed in U.S. Pat. No. 5,361,418.
As the median age of the population becomes older, there are more occasions for the treatment of hip disorders and there is still a need to improve the function of such orthoses and their component parts in this medical field in an economical manner, while addressing a comfort level for the patient to encourage maximize prolonged usage.